D
o not mount the instruments in or above the
fi
lling stream
.
M
ake sure
that you detect the product surface
,
not the in
fl
owing product
.
F
ig
.
13
:
I
n
fl
owing liquid
T
hrough the action of
fi
lling
,
stirring and other processes in the vessel
,
dense foams which considerably damp the emitted signals may form
on the product surface
.
I
f foams are causing measurement errors
,
the sensor should be used
in a standpipe or
,
alternatively
,
the more suitable guided radar sensors
(
TDR
)
should be used
.
G
uided radar is una
ff
ected by foam generation and is particularly
suitable for such applications
.
I
f there are strong air currents in the vessel
,
e
.
g
.
due to strong winds in
outdoor installations or air turbulence
,
e
.
g
.
by cyclone extraction you
should mount
VEGASON
61
in a standpipe or use a di
ff
erent
measuring principle
,
e
.
g
.
radar or guided radar
(
TDR
).
B
y using a standpipe
(
surge or bypass tube
),
the in
fl
uence of vessel
installations
,
foam generation and turbulence is excluded
.
S
tandpipes must extend all the way down to the requested min
.
level
,
as measurement is only possible within the tube
.
I
n
fl
owing medium
F
oam
A
ir turbulences
S
tandpipe measurement
VEGASON
61
•
4
…
20
m
A
/
HART
four
-
wire
17
4
M
ounting
28778
-
EN
-
081127